Fermentation Properties and Increased Health Functionality of Kimchi by Kimchi Lactic Acid Bacteria Starters

ABSTRACT Fermentation characteristics and health functionalities of kimchi by inoculating kimchi lactic acid bacteria (LAB) starters were studied. We manufactured single LAB starter kimchi (Lactobacillus plantarum pnuK, Lactobacillus plantarum 3099K, Leuconostoc mesenteroides pnuK), mixed LAB starter kimchi (Lb. plantarum pnu/Leu. mesenteroides pnuK, Lb. plantarum 3099/Leu. mesenteroides pnuK) with inoculum size of 106 CFU/g, as well as naturally fermented kimchi (NK), and fermented them for 6 days at 15°C. The pH and acidity of the early phase of fermentation were not different, but kimchi with the starters showed rapid changes in the pH and acidity from 2 days of fermentation. As the fermentation progressed, the level of total aerobic bacteria and Lactobacillus sp. increased similarly with or without Lb. plantarum (LP) inoculation. However, the level of Leuconostoc sp. was high in kimchi inoculated with Leuconostoc sp. starter. In the sensory evaluation test, kimchi with starters received higher overall acceptability scores than those of NK; mixed starter added kimchi earned the highest score. In DPPH and hydroxyl radical scavenging activity, kimchi with the starters exhibited higher activity than that of NK. In the MTT assay of HCT-116 and HT-29 human colon cancer cells, NK showed inhibition rates of 63.4 and 51.9%, but LPpnuK achieved 77.1 and 68.8%, respectively. This study showed that inoculating starters in kimchi increased in vitro antioxidant and anticancer activities, and single starter (LP) added kimchi revealed higher functionality than the kimchi with mixed starter. Kimchis with the starters effectively up-regulated the gene expressions of the pro-apoptotic gene of Bax, but down-regulated Bcl-2.